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Marine bioactive peptides (MBPs) are widely applied in functional foods and medicine industries. Several studies indicate that MBP consumption may play a vital role in the body's health due to their biological properties such as antioxidant, anti-inflammatory, and ACE-inhibitory activities. However, the majority of MBPs have numerous limitations, including bitter taste, stability, and unfavorable bioactivity. Recently, chemical and physical modifications have been commonly used to solve these limitations. Modification of MBPs, which involves using novel techniques, was discussed in this review. This review displayed that MBP properties, including biological activity, stability, and taste properties, were improved after modification mainly by encapsulation and chemical reaction. In particular, the results showed that the biological properties (antioxidant, anti-inflammatory, ACE-inhibitory, and antimicrobial activities) of the modified MBPs were higher than unmodified ones. In addition, the taste of MBPs, especially volatile flavor, was also enhanced after modification. Furthermore, modified MBPs may have to remain stable during food processing, storage, and in the host mouth and stomach for absorption in the small intestine. Therefore, modification of MBPs is an effective approach to protect and improve MBP properties. Finally, food matrix interactions and in vivo studies of modified MBPs are needed in the future. [ABSTRACT FROM AUTHOR]

This study aimed to immobilize β-galactosidase (β-GAL) into enhanced polystyrene (PS) electrospun nanofiber membranes (ENMs) with functionalized graphene oxide (GO). Initially, GO sheets were functionalized by salinization with 3-aminopropyl triethoxysilane (APTES). Then the ENMs (PS, PS/GO, and PS/GO-APTES) were prepared and characterized. Then, the β-GAL was immobilized in the different ENMs to produce the β-GAL-bound nanocomposites (PS-GAL, PS/GO-GAL, and PS/GO-APTES-GAL). Immobilization of β-GAL into PS/GO-APTES significantly improved enzyme adsorption by up to 87 %. Also, PS/GO-APTES-GAL improved the enzyme activity, where the highest enzyme activity was obtained at enzyme concentrations of 4 mg/L, 50 °C, and pH 4.5. Likewise, the storage stability and reusability of immobilized β-GAL were improved. Furthermore, this process led to enhanced catalytic behavior and transgalactosylation efficiency, where GOS synthesis (72 %) and lactose conversion (81 %) increased significantly compared to the free enzyme. Overall, the immobilized β-GAL produced in this study showed potential as an effective biocatalyst in the food industry. Figure. Schematic of representation functionalization graphene oxide (GO) by APTES and preparation of PS/GO-APTE ENMs for β-galactosidase immobilization via covalent bonding and high production of GOS yield. [Display omitted] • Successful bonding of APTES components to GO sheets was demonstrated. • PS/GO-APTES ENMs with higher hydrophilicity have increased enzyme adsorption. • Immobilized β-GAL demonstrated improved activity and stability in different settings. • PS/GO-APTES-GAL showed enhanced transgalactosylation activity over time. [ABSTRACT FROM AUTHOR]

This study aimed to immobilize β-galactosidase (β-GAL) into enhanced polystyrene (PS) electrospun nanofiber membranes (ENMs) with functionalized graphene oxide (GO). Initially, GO sheets were functionalized by salinization with 3-aminopropyl triethoxysilane (APTES). Then the ENMs (PS, PS/GO, and PS/GO-APTES) were prepared and characterized. Then, the β-GAL was immobilized in the different ENMs to produce the β-GAL-bound nanocomposites (PS-GAL, PS/GO-GAL, and PS/GO-APTES-GAL). Immobilization of β-GAL into PS/GO-APTES significantly improved enzyme adsorption by up to 87 %. Also, PS/GO-APTES-GAL improved the enzyme activity, where the highest enzyme activity was obtained at enzyme concentrations of 4 mg/L, 50 °C, and pH 4.5. Likewise, the storage stability and reusability of immobilized β-GAL were improved. Furthermore, this process led to enhanced catalytic behavior and transgalactosylation efficiency, where GOS synthesis (72 %) and lactose conversion (81 %) increased significantly compared to the free enzyme. Overall, the immobilized β-GAL produced in this study showed potential as an effective biocatalyst in the food industry. Figure. Schematic of representation functionalization graphene oxide (GO) by APTES and preparation of PS/GO-APTE ENMs for β-galactosidase immobilization via covalent bonding and high production of GOS yield. [Display omitted] • Successful bonding of APTES components to GO sheets was demonstrated. • PS/GO-APTES ENMs with higher hydrophilicity have increased enzyme adsorption. • Immobilized β-GAL demonstrated improved activity and stability in different settings. • PS/GO-APTES-GAL showed enhanced transgalactosylation activity over time. [ABSTRACT FROM AUTHOR]

In this study, modified sea Cucumber Peptides (SCP) were prepared by reacting with xylooligosaccharide (XOS) and alginate oligosaccharides (AOS) via glycation. Free radical inhibitory and inhibition of oxidative stress of modified SCP was evaluated using human hepatocellular carcinoma (HepG2) cells and zebrafish embryos. LC-MS analysis revealed that SCPs mainly consist of 40 active peptides, with an average molecular weight of 1122.168 Da and an average length of 11 amino acid residues. For amino acid composition, L-Asparagine, L-Methionine, and L-Aspartic Acid were dominant amino acids in SCP. The result showed that the antioxidant ability of SCP against 2,2-Diphenyl-1-picrylhydrazyl (DPPH), superoxide anion radical (O−2), and Hydroxyl Radical (OH) was significantly improved after modification. In HepG2 cells, the modified SCP showed stronger protection than native SCP native against H 2 O 2 -induced oxidative stress by enhancing cell viability and reducing radical oxygen species (ROS) generation. The inhibition effect of SCP was increased after modification with XOS and AOS by 13 % and 19 % respectively. Further studies displayed that the activity of antioxidative enzymes, including Superoxide dismutase (SOD), Glutathione Peroxidase (GPx), and catalase (CAT), was remarkably enhanced, whereas malondialdehyde (MDA) level was reduced compared with native SCP and H 2 O 2 -treated groups, thus, improving the intracellular antioxidant defenses. The gene expression analysis showed that the mechanism underlying the modified SCP protective effect may be linked with the capability to regulate Nuclear factor-erythroid factor 2-related factor 2 (NRF2) gene expression. The protective effect of modified SCP against H 2 O 2 in vitro was confirmed in vivo by reduced toxicity in zebrafish embryos via improvement of mortality rate, hatching rate, heart beating rate, and deformities of the zebrafish model. However, SCPAOS conjugate displayed greater antioxidant potentials compared to the SCPXOS, the different effects between SCPAOS and SCPXOS could be due to their different antioxidant activity. Thus, modified SCP could be potentially used as a novel nutraceutical in the preparation of anti-aging food and medicine. [ABSTRACT FROM AUTHOR]

In this study, modified sea Cucumber Peptides (SCP) were prepared by reacting with xylooligosaccharide (XOS) and alginate oligosaccharides (AOS) via glycation. Free radical inhibitory and inhibition of oxidative stress of modified SCP was evaluated using human hepatocellular carcinoma (HepG2) cells and zebrafish embryos. LC-MS analysis revealed that SCPs mainly consist of 40 active peptides, with an average molecular weight of 1122.168 Da and an average length of 11 amino acid residues. For amino acid composition, L-Asparagine, L-Methionine, and L-Aspartic Acid were dominant amino acids in SCP. The result showed that the antioxidant ability of SCP against 2,2-Diphenyl-1-picrylhydrazyl (DPPH), superoxide anion radical (O−2), and Hydroxyl Radical (OH) was significantly improved after modification. In HepG2 cells, the modified SCP showed stronger protection than native SCP native against H 2 O 2 -induced oxidative stress by enhancing cell viability and reducing radical oxygen species (ROS) generation. The inhibition effect of SCP was increased after modification with XOS and AOS by 13 % and 19 % respectively. Further studies displayed that the activity of antioxidative enzymes, including Superoxide dismutase (SOD), Glutathione Peroxidase (GPx), and catalase (CAT), was remarkably enhanced, whereas malondialdehyde (MDA) level was reduced compared with native SCP and H 2 O 2 -treated groups, thus, improving the intracellular antioxidant defenses. The gene expression analysis showed that the mechanism underlying the modified SCP protective effect may be linked with the capability to regulate Nuclear factor-erythroid factor 2-related factor 2 (NRF2) gene expression. The protective effect of modified SCP against H 2 O 2 in vitro was confirmed in vivo by reduced toxicity in zebrafish embryos via improvement of mortality rate, hatching rate, heart beating rate, and deformities of the zebrafish model. However, SCPAOS conjugate displayed greater antioxidant potentials compared to the SCPXOS, the different effects between SCPAOS and SCPXOS could be due to their different antioxidant activity. Thus, modified SCP could be potentially used as a novel nutraceutical in the preparation of anti-aging food and medicine. [ABSTRACT FROM AUTHOR]

Effecient green tools of β-(3,4-dichlorophenyl-acrylic acid, thioglycolic acid and β-(2-oxopyrrolidin-1-yl) ethanol under ultrasonic and microwave-assisted irradiation (MW-US) as found to be a simple approach for preparing interesting Spiro derivatives. A novel class Spiro-pyrrolidine-2,3'-thieno[2,3-d]pyridazine derivatives (2–6) were efficiently synthesized via one-pot multicomponent reactions. Ethoxy acetyl Spiro pyrrolidine-2,3'-thieno[2,3-d]pyridazin-hydrazide (5) assessed as ecofriendly microbicidal and insecticidal activities to establish a structure-activity relationship. Elemental analysis and spectroscopic data were used to describe the structures of all synthesized products. The Spiro-heterocyclic compounds are exclusive non-planar structures and branded for binding to biomolecules. The microbicidal and insecticidal activities of the compounds were investigated on ATCC coded test microorganisms upon the applied dose and time was studied through two kinetic study. The interaction with these antibacterial and insect's third instar larvae was medicinal and economically valuable. The preliminary testing demonstrated flourishing microbicidal capability to prevent the growth of threatening pathogenic bacteria as well as blossoming insecticidal efficacy. Moreover, Molecular docking and density functional theory simulations can be used to validate the experimental results. Also, we utilized the docking approach with secondary bacterial infection indicated that Ethoxy acetyl Spiro hydrazide (5) and Spiro arylidene hybrid (6) have exerted the strongest docking binding value against the active sites of 6LU7. [ABSTRACT FROM AUTHOR]

The present work described a novel synthesis of spiro[indoline-3,3′-pyrazol]-2-one derivatives 2, 4, 5, and 7 via a one-pot reaction of chalcones or β-aroyl acrylic acid 1a–c, isatin, and hydrazine derivatives e.g. hydrazine hydrate, methyl hydrazine, phenylhydrazine or acetohydrazide in sonicated reaction condition. The unexpected product 1,3-oxazino[3,2-a]indol-10-yl-ethanone derivative 6 can be generated instead of N-acetyl spiro[indoline-3,3′-pyrazol]-2-one as desired. Also, the Spiropyrazole-fused furanone and pyridazinone ring can be made. Owing to their unique 3-dimensional structures, spirooxindoles have been found as lucky chemotypes for antiviral drug enhancement in an attempt to achieve these spiropyrazole derivatives 2–10 with hydrophobic groups. Furthermore, the density functional theory (DFT) was used to elucidate the electronic and structural features of spiropyrazole derivatives and their reactive species, which supports the proposed mechanism of antibacterial and antiviral capabilities. [ABSTRACT FROM AUTHOR]

• GISs-based rooftop solar photovoltaic potential estimation approaches are reviewed. • Approaches are classified as sampling, geostatistics, modeling, and machine learning. • All applications and limitations of each approach are reviewed and discussed. • Machine learning is a promising approach for large-scale rooftop solar PV estimates. In urban environments, decentralized energy systems from renewable photovoltaic resources, clean and available, are gradually replacing conventional energy systems as an attractive source for electricity generation. Especially with the availability of unexploited rooftop areas and the ease of installation, along with technological development and permanent cost reductions of photovoltaic panels. However, the optimal use of these systems requires accurate estimates of supply (rooftop solar photovoltaic potential) and the design of an intelligent distributed-system integrated with power grids. Geographic information systems (GISs)-based estimation is justified as a promising approach for estimating rooftop solar photovoltaic potential, in particular, the possibility of combining GISs with LiDAR (Lighting-Detection-And-Ranging) to build robust approaches leading to accurate estimates of the rooftop solar photovoltaic potential. Accordingly, this study aims to present a comprehensive review of GISs-based rooftop solar photovoltaic potential estimation approaches that have been applied at different scales, including countries. The study classified GISs-based approaches into sampling, geostatistics, modeling, and machine learning. The applications, advantages, and disadvantages of each approach were reviewed and discussed. The results revealed that GISs-based rooftop solar photovoltaic potential estimation approaches, can be applied to the large-scale spatial-temporal assessment of future energy systems with decentralized electrical energy grids. Assessment results can be employed to propose effective-policies for rooftop photovoltaic integration in built environments. However, the development of a new methodology that integrates GISs with machine learning to provide an accurate and less computationally demanding alternative to LiDAR-based approaches, will contribute significantly to large-scale estimates of the solar photovoltaic potential of building rooftops. [ABSTRACT FROM AUTHOR]

• The review focuses on energy prediction techniques for large-scale buildings. • Five types of energy demand determinants in large-scale buildings were analyzed. • The techniques are classified the black, white, and grey-box based approaches. • A variety of energy-related applications, including energy-mapping were analyzed. • The hybrid models are suitable for energy predictions in large-scale buildings. Building energy prediction techniques are the primary tool for moving towards sustainable built environments. Energy prediction models play irreplaceable roles in making energy policy and the development of the building sector. This paper presents a comprehensive review of the prevailing prediction techniques used in large-scale building energy applications under different scopes and different archetypes, including black-box, white-box, and grey-box based methods. Additionally, the advantages and disadvantages of the applications of those approaches are compared and discussed in the context of large-scale buildings. The review results show that prediction techniques have addressed a variety of large-scale building energy related-applications, such as energy consumption forecasting and prediction, energy consumption profiling, energy mapping and benchmarking of buildings. However, there are still some research gaps that require more attention such as the inclusion of occupant behavior in white-box based models and the explicit representation of end-uses in black-box based models. Significantly, this review concludes with a few key tasks for modification of the current prediction approach framework, which can help with forecasting future energy use changes of specific buildings during the retrofit process or inclusion of renewable energy technology. This would assist in developing an appropriate strategy for the sustainability of the built environment. [ABSTRACT FROM AUTHOR]

Development of energy prediction models plays an integral part in management and enhancement of the energy efficiency of buildings, including carbon emission reduction. Simplified and data-driven models are often the preferred option when detailed information of simulation is not available and the fast responses are required. This study developed data-driven models for predicting electricity and gas consumption in London's residential buildings at the middle super output areas (MSOA) and lower super output areas (LSOA) with multilayer neural network (MNN), multiple regression (MLR), random forest (RF), and gradient boosting (GB) algorithms, and factors related to socio-demographic, economic, and building characteristics were used as predictors. The results revealed that building characteristics, household income, and the number of households were the most important predictors of electricity and gas consumption. We also found that MNN models have outperformed MLR, RF and GB models in electricity and gas consumption prediction at MSOA and LSOA levels, with R2 values over 0.99 for the electricity consumption model. In summary, this study shows that the MNN models can be a useful tool to assist the formation of energy efficiency policies in buildings at MSOA and LSOA levels. • Four types of data-driven residential energy models at district scales in London were developed. • The performance of the developed models was validated against the independent testing data. • Multilayer neural network models outperformed the other three models. • Model inputs from UK census survey were effective in the model development. [ABSTRACT FROM AUTHOR]

In food safety implementation, bacterial inactivation is an imperative aspect of hygiene and sanitation. Studies on lithium magnesium silicate (LMS) hydrosol incorporated with slightly acidic electrolyzed water (SAEW) for decontamination of pathogenic bacteria are limited. This present study aimed to investigate the bactericidal efficacy of LMS hydrosol incorporated with SAEW against Escherichia coli. Optimum combination conditions of SAEW, hydrosol concentration, and available chlorine concentration (ACC) were optimized by response surface methodology under the central composite design against the growth of E. coli. The optimum combination conditions of exposure time, hydrosol concentration, and ACC were 9.5 minutes, 1.7%, and 20.5 ppm, respectively. The results showed that the increase in ACC led to inactivation in the survival of E. coli compared with the control (p<0.05). It can be concluded that the best combination percentage between SAEW and hydrosol ranged from 1.5-1.7%, in which E. coli was reduced by 4.50 log10 CFU/mL at an ACC of 9.94 ppm. When increasing the ACC to 14.84 ppm, E. coli was reduced by 4.51 log10 CFU/mL compared with the initial number of bacteria (8.20 log10 CFU/mL) in the control group. The number of bacteria was undetected after increasing ACC to 19.93, 25.15, and 29.88 ppm at 10 min. This study suggests that LMS hydrosol incorporated with SAEW could potentially be used as an effective sanitizer. [ABSTRACT FROM AUTHOR]

Synthesis of ethyl acetate (EA) using lipase as a catalyst, as an environmentally-friendly process, has attracted considerable attention. However, the slow rate of enzymatic reaction and higher cost limit its applications. Ultrasound irradiation (UI) is known as an effective tool for accelerating the rate of enzymatic reaction under mild conditions. To attain maximum yield, it is crucial to understand the effect of UI on EA synthesis and the underlying mechanism. Therefore, the present study investigated the effect of UI on lipase-catalyzed ethyl acetate synthesis. The results clearly demonstrated that UI could remarkably accelerate the process of lipase-catalyzed synthesis of ethyl acetate compared with mechanical shaking. The optimal conditions of ultrasound-assisted reaction by using Novozyme 435® were 6% enzyme loading, 4:1 molar ratio of ethanol to acetic acid, 150 W & 28 kHz ultrasonic power and frequency, respectively. Bi-bi ping-pong model was employed to give a deep insight into the underlying mechanism of the beneficial effect of UI. It was found that Vmax under UI was elevated by 143% compared with that under mechanical shaking. Application of UI could decrease Kacetic acid and Ki ethanol while increase Kethanol and Ki acetic acid. In conclusion, the present study addresses that UI could remarkably accelerate the process of lipase-catalyzed synthesis of EA compared with mechanical shaking, and kinetic model results explained why ultrasound can significantly speed up lipase catalyzed synthesis of ethyl acetate, which may help to improve the industrial application potential of ethyl acetate biosynthesis. [ABSTRACT FROM AUTHOR]

The interaction between epigallocatechin gallate (EGCG) and whey protein isolate (WPI) under various pH and ion concentrations conditions was examined by ultraviolet-visible spectrophotometer and fluorescence spectra. The results showed that EGCG with WPI was linked mainly by electrostatic force, and EGCG caused the fluorescence quenching of WPI through a static quenching. Furthermore, in vitro static release results showed that the release process of EGCG from EGCG-WPI gel in release medium of different pH and ion concentrations follows the Korsmeyer-Peppas model and conform to the non-Fick diffusion law. Finally, the binding constant KA and the constant release Kapp kinetic model were established. The model followed the equation LnKA=A - 1 n LnKapp. [ABSTRACT FROM AUTHOR]

In this study, two endophytic actinomycetes isolates Oc-5 and Acv-11, were isolated from healthy leaves of medicinal plant Oxalis corniculata L. These isolates were identified as Streptomyces zaomyceticus Oc-5 and Streptomyces pseudogriseolus Acv-11 using 16S rRNA gene sequence. Biomass extract of these strains were used as a greener attempt for synthesis of copper oxide nanoparticles (CuO-NPs). The synthesized NPs were characterized by UV–Vis spectroscopy, Fourier transform infra-red (FT-IR) spectroscopy, X-ray diffraction (XRD)‚ transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS). Green synthesized NPs showed surface plasmon resonance (SPR) absorption band at 400 nm, crystalline nature, spherical-shaped with an average size of 78 nm and 80.0 nm for CuO-NPs synthesized using strain Oc-5 and Acv-11, respectively. The bioactivities of CuO-NPs were evaluated. Results revealed that CuO-NPs exhibited promising antimicrobial activity against prokaryotic and eukaryotic microbial cells (Gram positive bacteria, Gram negative bacteria, unicellular and multicellular fungi). In addition, it showed antimicrobial potential against phyto-pathogenic fungal strains Fusarium oxysporum, Pythium ultimum, Aspergillus niger and Alternaria alternata. We further explored the in vitro antioxidant activity and cytotoxicity for biosynthesized CuO-NPs. The results revealed that‚ scavenging and total antioxidant activity for NPs synthesized using Streptomyces pseudogriseolus Acv-11 was better than those synthesized by Streptomyces zaomyceticus Oc-5. Also, the morphological changes and cell viability for Vero and Caco-2 cell line due to NPs treatments were assessed using MTT assay method. Furthermore, Larvicidal efficacy against Musca domestica and Culex pipiens was evaluated. The results obtained in this study clearly showed that biosynthesized CuO-NPs exhibited effective bioactivity and, therefore, provide a base for the development of versatile biotechnological applications soon. [ABSTRACT FROM AUTHOR]